In a large saucepan, sauté onion and green pepper in butter until tender. Add broth and cubed potatoes. Bring to a boil. Reduce heat; cover and simmer for 15 minutes or until potatoes are almost tender. Stir in jalapeno, mustard, basil, paprika and red pepper flakes. Add corn, green onions and 1½ cups of milk. Bring to a boil. In a separate bowl, combine all-purpose flour and remaining ½ cup milk, stirring until smooth. Gradually add mixture to soup. Bring to a boil. Cook and stir for 2 minutes or until thickened and bubbly